Middle of Centres

A Maths Starter of The Day

What are the coordinates of the two points that the blue point is exactly in the middle of?


Now for the advanced student:

Which point is in the middle of the centres of enlargements?

If you can't see the images above it may be because you do not have a recent version of the Flash Player installed or that your device (such as the iPad) cannot show Flash diagrams.

The large red shape is an enlargement of the small red shape.
The large blue shape is an enlargement of the small blue shape.
[One small square represents one unit]

Teacher: Right click the diagram to zoom in.




Topics: Starter | Coordinates | Enlargements | Loci

  • Set 1 (maths geeks), Ecclesbourne School
  • We really enjoyed this starter, thank you.
  • Cathryn, China
  • It's a very good practice. Thank you.
  • Maggie, Devon
  • Engaging starter, numbers on axes need to be bigger.

    [Transum: Thanks for the suggestion Maggie. It has now been done.]
  • Buthayna,
  • 'Thank you. I used my own set of axes, but thank you for the idea.'.

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This starter has scored a mean of 3.0 out of 5 based on 168 votes.

Previous Day | This starter is for 25 July | Next Day


(3,3) and (-1,-1)

For the advanced student:


Note to teacher: Doing this activity once with a class helps students develop strategies. It is only when they do this activity a second time that they will have the opportunity to practise those strategies. That is when the learning is consolidated. Click the button above to regenerate another version of this starter from random numbers.

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Laptops In Lessons

Teacher, do your students have access to computers?
Do they have iPads or Laptops in Lessons?

Whether your students each have a TabletPC, a Surface or a Mac, this activity lends itself to eLearning (Engaged Learning).

Laptops In Lessons

Here a concise URL for a version of this page without the comments.


Here is the URL which will take them to a related student activity.


Student Activity


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